Smudge-resistant pressure-sensitive transfer element for placing smudgeresistant marks



T PRESSURE-SENSITIVE TRANSFER ELEMENT FOR PLACING SMUDGE-FRESISTANT MARKS Filed Sept. 9, I959 1.! Tam/5H5? SHEET 2/ co y swam- INVENTORS Douglas A. New/77am ffg r olci 17E Dixon WWW ATTQfA/EYS 3,062,676 Patented Nov. 6, 1962 ice SMUDGE RESTSTANT PRESS SENSITIVE TRANSFER ELEMENT FUR PLACING SMUDGE- RESRSTANT MARK Douglas A. Newman, Glen Cove, and Harold F, E.

Dixon, Douglaston, N.Y., assignors to Columbia Ribbon and Carbon Manufacturing (Company, Inc, Glen Cove, N.Y., a corporation of New York Filed Sept. 9, 1959, Ser. No. 838,920 7 Claims. (Cl. 11.7-36.4)

This invention relates to transfer writing and particularly to the placing of marks and indicia by means of printing or writing pressure or a type blow, acting through a pressure-sensitive transfer sheet of the carbon paper t e.

lhe present application is a continuation-in-part of application Serial No. 689,635, filed October 11, 1957, now Patent No. 2,912,344, granted November 10, 1959.

Transfer sheets of the carbon paper type have, of course, been known and used for many years. Lately, however, the placing of various types of record marks on copy sheets or cards to be handled and sensed by data processing equipment has become a matter of increasmg interest, and the use of paper sheets or typewriter ribbons as the medium for placing carbon spots of the required properties has been suggested, one such suggestion appearing in the patent to Mumma, No. 2,744,031.

It has been found, however, that most of the pressure transfer layers, as currently prepared, are lacking in certain respects when an attempt is made to adapt them to data processing use. While the marks made are of adequately permanent nature considered in the sense of ordinary carbon copy use and will remain sufiiciently legible under most conditions, it has been found that there is a slight tendency to smudge and spread if the marked sheet is handled a great deal, or used with the ordinary sheet or card feeding and handling equipment encountered in data processing machinery. Also in conventional practices, it is diilicult to control the smudging of the copy sheets or cards, in the transfer process due to the dirty surface of the transfer sheets. When this smudging occurs, the reliability with which the true mark can be automatically sensed is severely impaired, even though the impairment is sometimes comparatively slight by visual standards, and false indications are picked-up due to contact of the dirty, uncoated surface of the transfer sheet with the record caused by handling during the transfer process.

The objects of the present invention are to provide a transfer element which is smudge-free and clean to the touch, has excellent adhesion, even for greasy surfaces, and is of such character that the transferred spot or image when formed will be substantially proof against smudging and such that the marked card or sheet will pass readily through ordinary handling equipment without the spots sustaining any change sufficient to affect the accuracy of the sensing operation.

It is a feature of the present invention that the foregoing objects are brought about by constructing the trans fer sheet with a coating having at least three distinct layers or strata, simultaneously transferable from the carrier sheet in a substantially stenciling fashion, in which the bottom stratum or layer nearest the carrier sheet is one having smudge-resistant properties. The middle layer is pigmented and designed for automatic sensing, and the top layer is similar to the bottom layer in that it has smudge-resistant properties. These properties of smudgeresistance may be due either to the absence from the layer of material to which the sensing device will react, so that even though the layer is partially displaced by handling, the displaced portion will not affect the sensing means, or to the character of the layer as being relatively hard and of low adhesiveness so that even though charged with a type of material to which the sensing device in question will react, it is not subject to ready displacement from the spot where applied or both.

By reason of the placement of the bottom smudgeresistant layer adjacent the carrier sheet, the image formed when the coating is transferred by pressure from the carbon paper to the copy sheet has an exposed surface which normal contact with handling devices does not seriously aifect, so that, even though the sheet has been fed and handled, there is assured a reaction at the sensing means which is the same as that which the spot would have brought about in its freshly-transferred condition.

It will be readily appreciated that the principles of the invention can be applied whether the transfer layers are arranged to deposit spots suitable for sensing visually or by photoelectric means, by magnetic means, or by any other means sensitive to special material in the coating. Examples of various types will appear as the description proceeds.

In the drawing:

FIGURE 1 is a fragmentary diagrammatic section to an enlarged scale of a pressure-sensitive transfer element according to one form of the invention.

FIGURE 2. is a fragmentary diagrammatic section to an enlarged scale of a copy sheet having thereon a spot formed by transfer from that element of FIG. 1.

Referring to the drawing, the transfer element of the present invention comprises a carrier sheet or strip 11 of paper, regenerated cellulose, cellulose acetate, or a similar thin, flexible material. On one surface of the sheet or strip 11 is formed a transfer coating 13 which is characterized particularly by the fact that it is made up of three strata or layers 15, 16, and 17. The base layer 15 which lies next to the carrier 11 and the top layer 17 are the layers of material having smudgeresistant properties as hereinbefore mentioned and defined. The base layer has placed on its surface the middle layer 16 which is so constituted as to firmly bond to the base layer 15 and the top layer 17. Preferably the layers 15, 16 and 17 are somewhat commingled adjacent their meeting surfaces to effect this bond, as indicated by the character of the cross-hatching in FIG. 1. However, this commingling is not essential and may be dispensed with providing an adequate bond is furnished in any suitable manner whereby the three layers may cling together and act as a unit.

The nature of the composite layers 15, i6 and 17, i.e. the coating 13, is such that when the carrier 11 is impressed by a stylus or struck by a type, substantially all of the material of coating 13 in the area pressed or struck will be transferred to an adjacent copy sheet, leaving little, if any, on the transfer carrier. In other Words, the coating has the property known in the art as stenciling. The dual character of the coating 13' lends itself very well to this purpose since the layer 15 can be formulated to have a particular degree of adhesiveness for the carrier 11 to promote ready release under pressure without division of the coating, and the layer 17 may be formulated to have a more pronounced adhesiveness for the copy paper or receiving sheet normally used whereby to bring about the stenciling transfer. To effect this adhesiveness tackifying agents may be incorporated into layer 17, such as Indopol T3()0 or Vistac which are polybutene compositions, or even large amounts of beeswax which is naturally tacky. While, in most cases, it is preferable to have the layer 15 separate from the foundation 11 almost entirely, this is not always essential, and the term stenciling is understood to include cases where only a portion of layer may be transferred, so long as it is sufficient to be effective for the purposes intended.

The FIG. 1 form is at present found most useful in systems employing visual reading, or for automatic photoelectric or magnetic sensing. For visual use or for photoelectric sensing a pigment having light reflecting or absorption value may be carried in the middle layer to, and the same would be so colored as to contrast sharply with the color of the cards or copy sheets on which it is to be used. Carbon black, for example, would serve effectively if used on light colored cards. In one embodiment of the present invention, the layers 15 and 17 are compounded with little or no pigment so as to be substantially transparent. In another embodiment of the present invention the bottom layer 15 on the transfer sheet, which becomes the top layer on the record upon transfer, or the top layer 17 on the transfer sheet which becomes the bottom layer on the record may contain a masking pigment, Le, a pigment which masks or hides the color of the pigment of the middle layer 16 from vision. For instance in the preparation of pay check records or billing records or secret documents, a masking pigment, such as titanium dioxide, commercially available by the name Titanox, may be incorporated in base layer 15. Upon transfer to a white sheet the image cannot clearly or easily be seen visually but is clearly detectable by, for instance, magnetic means where magnetic oxide is incorporated into middle layer 16. Example II below shows this embodiment. The preferred use of such masking pigments, however, is to hide the dark color of the transfer sheet by including pigment in the top layer 17 such as titanium dioxide or zinc oxide. In this manner the transfer sheet appears white but yields a dark copy on transfer. Example I shows this embodiment when titanium dioxide or zinc oxide is used as the pigment in the top layer.

An still another embodiment of the present invention comprises the addition of a tint color to the base layer 15 which together with the dark pigment of the middle layer 16 gives an overall lightened color to the transfer paper. However on transference the colors apparently coalesce under pressure and the tone of the stronger pigment of layer 16 is emphasized yielding a stronger colored copy than would have been expected from the light appearance of the transfer sheet. Here, for instance, a blue pigment or a pink pigment may be incorporated into base layer 15 and a carbon black or red pigment respectively may be incorporated into the middle layer. As light blue pigments may be mentioned Ultramarine or Phthalocyanine Blue. As pink pigments may be mentioned Lake Red C or Sodium Lithol Red reduced with zinc oxide. The final transfer paper then has a light colored appearance but upon transfer under pressure the dark black or red color predominates to give a strong colored copy.

When the pressure transfer has been effected in the normal way, a product as seen in FIG. 2 will result, having an image 23, the bottom layer 17a, previously the top layer of the transfer sheet, lies against and is adhered to a copy sheet 21, the middle layer 16a, and the top layer 15a which was previously the bottom layer of the transfer sheet. It will be seen that the layer 15a protects the layer 16a effectively against being disturbed or spread. This is true whether the layer 15a is itself soft enough to be disturbed or spread by random contact with feeding or handling devices, or so hard as to be substantially impervious to such spreading, and the layer 16a remains in its original position precisely as placed. Whether the layer 15a is unencumbered with possibly deleterious pigment, or hard enough to resist displacement, or both, it is clearly compounded to be smudgeresistant as the term is defined above and used throughout this description.

Included in the term pigment, of course, are pulverulent materials of all kinds whether used for their light response or not. In case the pigment is of magnetic particles, iron oxide for example, the image or mark 23 will be capable of being sensed by magnetic pick-up means, and in this instance layers 17 or 15a also be pigmented with a masking pigment such as titanium dioxide if desired, so long as the pigment used is nonnagnetic and so that the layer 15a, relative to the magnetic sensing means to be used, will be fully smudge-resistant.

Examples of mixtures suitable for preparing a transfor sheet in accordance with FIG. 1 are as follows.

EXAMPLE I (Formula 1) Base Lcryer Ingredients: Parts by weight Carnauba wax 45.0 Ceresin 4.0 Lanolin 6.0 Mineral oil 20.0

(Formula 2) Middle Layer Carnauba wax 45.0 Lanolin 6.0 Mineral oil 20.0 Carbon black 12.0

(Formula 3) Top Layer Carnauba wax 45.0 Indopol H300 (tacky viscous liquid mixture of polymerized butene isomers) 6.0 Beeswax 6.0 Mineral oil 20.0 Pigments, if desired 10.0 to 20.0

EXAMPLE II (Formula 4) Base Layer Ingredients: Parts by weight Carnauba wax 45.0 Ceresin 4.0

Lanolin 6.0 Mineral oil 20.0 Titanium dioxide 10.0

(Formula 5) Middle Layer Carnauba wax 45.0

Lanolin 6.0

Mineral oil 18.0 Magnetic iron oxide 18.0

Top layer: Formula 1 or Formula 3 as given above.

The above examples are formulated for use particularly in connection with carrier sheets of paper of a type known in the art as carbonizing kraft.

If a coating similar to Example I or II were to be used for placing on a smooth film carrier such as regenerated cellulose, then the base layer 15 would preferably have a slightly different formulation, e.g. as follows.

(Formula 6) Base Layer Ingredients: Parts by weight Carnauba wax 45.0

Ceresin 4.0

Lanolin 6.0 Mineral oil 15.0 Pigment (if any) 10.0

In the case of application of the coating 13 to a relatively smooth, non-absorptive carrier, it may sometimes prove advantageous, in lieu of changing the formulation, to pretreat the surface of the carrier with an extra conditioning coating as taught in US. Patent No. 2,508,725.

As a slight modification of the form of the invention shown in FIGS 1 and 2, in some instances it is found desirable to make only the base layer 15 and the top layer 17 of normally transferable compositions, while the middle layer 16 is a tenacious, non-adhesive film which, of itself, would not transfer. However, the characteristics of the base layer 15 and the top layer 17 override those of the layer 16, and in transferring under pressure, the image portion of layer 15 aids in the breaking away of a similar portion of the layer 16 and layer 17 effects the adhesive attachment of the same to the copy sheet 21.

Examples of mixtures operating in this fashion are as follows.

EXAMPLE III Base layer: Formula 1 or Formula 4 as given above.

(Formula 7) Middle Layer Ingredients: Parts by weight YXSG polyvinyl butyrate 30 Methanol 510 Nigrosine base 3 Carbon black 27 Top layer: Formula 1 or Formula 3 as given above.

EXAMPLE III-A Base layer: Formula 1 or Formula 4 as given above. (F rmula 7!!) Middle Layer Ingredients: Parts by weight Carbon tetrachloride 100 Gilsonite 10 Top layer: Formula 1 or Formula 3 as given above.

In this example the gilsonite acts not only as the binder and film former but as the coloring agent as well. However, additional pigment in reasonable amounts may be added to the formula if desired.

EXAMPLE IV Base layer: Formula 1 or Formula 4 as given above. (Formula 8) Middle Layer Ingredients: Parts by weight YXSG polyvinyl butyrate 3O Methanol 510 Nigrosine base 3 Magnetic iron oxide 27 Top layer: Formula 4 or Formula 1 as given above.

EXAMPLE IV-A Base layer: Formula 1 or Formula 4 as given above.

(Formula 8a) Middle Layer Ingredients: Parts by weight Carbon tetrachloride 100 Gilsonite 10 Magnetic iron oxide Top layer: Formula 4 or Formula 1 as given above.

It will be understood that the examples given above are illustrative only and that various types of formulations may be employed within the scope of the present inventron.

For example, a suitable amount of an ultra-violet absorbing agent may be incorporated into any of the aforesaid base layers to protect the formed image after transfer against the damaging effects of light. Conventional ultra-violet absorbing agents may be employed, such compounds being generally carbonyl-containing compounds such as benzoyl resorcinol, benzophenone and substituted benzophenones such as dihydroxy benzophenone and 2,2- dihydroxy, 4-n-octoxy benzophenone sold under the name Cyasorb UV-314 by American Cyanamid. Salicylate and benzoate esters such as phenyl salicylate (salol) and resorcinol dibenzoate may also be used with great success. Proportions within the range of 0.001 to 5.0 percent based upon the total weight of the base layer yield good results while a preferred range lies between 0.1 to 2.0 parts by weight. Likewise a tint color of, for instance, pink or blue may be incorporated in the base layer as the pigment in Formula 6 above to give the transfer paper a lighter colored appearance. Also the compositions for the various layers may be based primarily on the type of oil and wax hot melt mixture which is conventionally used to prepare pressure-sensitive transfer sheets, or may be compounded as resinous base mixtures rendered. fluid for coating by being suspended in volatile solvent liquids as shown in copending application Serial No. 503,830, filed April 25, 1955, and now abandoned, and in US. Patents No. 2,872,340, issued February 3, 1959, and No. 2,810,661, issued October 22, 1957. In this connection it should be pointed out that, in general, the layers cast from a mixture of a resinous base suspended in volatile solvent, when properly compounded, perform especially Well as the layer 16 which is designed to be resistant to mechanical spreading or displacement, such as the harder form of layer 16 typified by Formula 7, and that layers cast from a waxy or wax-oil hot melt mixtures, when properly compounded, serve especially well as the transfer-promoting smudge-proofing layers, although it will be understood that either type of layer can evolve from either base material by appropriate compounding. As resinous base materials which have been used with success in the base, middle or top layers may be mentioned ethyl cellulose, cellulose esters such as the acetate and nitrate, polyvinyl esters such as the butyrate and many others.

In place of the waxes named in the examples, conventional vegetable, mineral or synthetic waxes may be used such as paraffin, microcrystalline wax, carbowax, spermacetti, raw montan wax alone or in combination with each other or with lanolin and/ or mineral oil. Conventional fillers may also be included.

Integration of the layers at the interface may be effected by various suitable treatments, such as the softening of the surface of the base and middle layers by solvent treatment just prior to depositing the middle and top layers respectively, or preferab'y by subjecting the coated sheet to controlled heating or fusion just after the middle and top layers have been placed. A particularly effective method of integration of the layers resides in quickly heating the transfer paper, after the layers have been applied, to the melting of fusion point of the wax for a short period of time to allow the layers to completely blend at the interface. Temperatures within the range of 220 C. have been used, with the preferred range lying between 180 C. and 200 C. This fusion step results in an improvement of the smudge-resistance of the transfer paper as well as that of the formed image.

From the foregoing description it can be seen that a novel coated, smudge-proof, clean handling pressure-sensitive transfer element of the carbon paper type has been provided in which the coating comprises a base layer, a middle layer and a top layer which are simultaneously transferable in stenciling fashion from the carrier to an adjacent copy sheet, and in which the base layer 15, by virtue of its properties, either of lack of deleterious pigmentation effective on the sensing device to be used, or of hardness and resistance to mechanical displacement, is likewise thoroughly smudge-resistant. A transfer element of this character is capable of producing novel images and spots in which the transfer sheet layers are inverted and which have excellent properties of adhesion, even for greasy or dirty surfaces, and accordingly have a high degree of resistance to smudging so as to perform reliably in data processing equipment in spite of the feeding and handling to which they will normally be subjected prior to sensing. Thus, in the case of the processing of checks or receipts which are greasy or oily due to being handled and carried by factory Workers or mechanics etc., the transfer papers of the instant invention furnish excellent properties of adhesion for the greasy surfaces and insure that the images transferred will not flake off.

The term sheet as used herein applies to flexible foundation membranes of any sort in coated or uncoated condition, whether of limited length, or of extended length, and in this connection includes items sometimes referred to as webs, strips, or ribbons.

Variations and modifications may be made within the scope of the claims and portions of the improvements may be used without others.

We claim:

1. As a new article of manufacture, a smudge-resistant pressure-sensitive transfer element of the carbon paper type designed for the placing of smudge-resistant images comprising a flexible foundation sheet having thereon three mutually adhering layers which are simultaneously locally transferable from the foundation to a copy sheet in a substantially stenciling manner in response to a blow or pressure, the middle layer being charged with pig-ment designed for automatic sensing, the base layer adjacent the surface of the sheet having readily releasable contact therewith and containing a pigment designed for masking the pigment of the middle layer of said images, and the top layer being of smudge-resistant character and having pronounced adhesiveness for said copy sheet.

2. As a new article of manufacture, a smudge-resistant pressure-sensitive transfer element of the carbon paper type designed for the placing of smudge-resistant images comprising a flexible foundation sheet having thereon three mutually adhering layers which are simultaneously locally transferable from the foundation to a copy sheet in a substantially stenciling manner in response to a blow or pressure, the middle layer being charged with magnetic pigment, the base layer adjacent the surface of the sheet having readily releasable contact therewith and containing a pigment designed for masking the magnetic pigment of the middle layer of said images, and the top layer being of smudge-resistant character and having pronounced adhesiveness for said copy sheet.

3. As a new article of manufacture, a smudge-resistant pressure-sensitive transfer element of the carbon paper type comprising a flexible foundation sheet having thereon three mutually adhering layers which are simultaneously locally transferable from the foundation to a copy sheet in a substantially stenciling manner in response to a blow or pressure, the base layer adjacent the surface of the sheet having readily releasable contact therewith and containing a light colored pigment designed to lighten the appearance of the pigment of the middle layer, said middle layer containing a pigment designed for automatic sensing, and the top layer being of smudge-resistant character and having pronounced adhesiveness for said copy sheet.

4. A smudge-resistant record-carrying element for use with automatic sensing equipment comprising a foundation sheet, and a local sensible carbon paper mark thereon containing three mutually adhering layers, a top, middle and bottom layer, the one lying farthest from the foundation sheet being the top layer and containing pigment designed for masking the pigment of the middle layer and the one adjacent the foundation sheet being the bottom layer and having pronounced adhesiveness for said foundation sheet, both layers being of smudge-resistant character, and the middle layer being charged with pigment designed for automatic sensing.

5. A smudge-resistant record-carrying element for use with automatic sensing equipment comprising a foundation sheet, and a local sensible carbon paper mark thereon containing three mutually adhering layers, the one lying farthest from the foundation sheet being the top layer and containing pigment designed for masking the pigment of the middle layer and the one adjacent the foundation sheet being the bottom layer and having pronounced adhesiveness for said foundation sheet, both layers being of smudge-resistant character, and the middle layer being charged with magnetic pigment.

6. As a new article of manufacture, a smudge-resistant pressure-sensitive transfer element of the carbon paper type designed for the placing of smudge-resistant images comprising a flexible foundation sheet having thereon three mutually adhering layers which are simultaneously locally transferable from the foundation to a copy sheet in substantially stenciling manner in respense to a blow or pressure, the middle layer including a pigment designed for automatic sensing, and being sufficiently tenacious and free from adhesiveness to be normally, of itself, nontransfera-ble under a blow or pressure, the base layer adjacent the surface of the sheet containing a pigment designed for masking the pigment of the middle layer of said images and having readily releasable contact therewith and being relatively soft and adhesive and therefore subject to possible displacement by physical contact, whereby to provide for local transfer of said three layers under pressure, and the top layer being of smudge- -resistant character and having pronounced adhesiveness for said copy sheet.

7. As a new article of manufacture, a smudge-resistant pressure-sensitive transfer element of the carbon paper type designed for the placing of smudge-resistant images comprising a flexible foundation sheet having thereon three mutually adhering layers which are simultaneously locally transferable from the foundation to a copy sheet in a substantially stenciling manner in response to a blow or pressure, the middle layer including a magnetic pigment, and being sufliciently tenacious and free from adhesiveness to be normally, of itself, non-transferable under a blow or pressure, the base layer adjacent the surface of the sheet containing a pigment designed for masking the pigment of the middle layer of said images and having readily releasable contact therewith and being relatively soft and adhesive and therefore subject to possible displacement by physical contact, and the top layer being of smudgeresistant character and having pronounced adhesiveness for said copy sheet whereby to provide for the local transfer of said three layers under pressure.

References Cited in the file of this patent UNITED STATES PATENTS UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent N0. 3,062,676 November 6, 1962 Douglas A. Newman et al.

It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

Column 2, line 29, for "that" read the line 51, for "layers" read layer line 66, for '"T-300'I read H-SOO column 3, line 37, for .An" read And column 4, liq e 31,. for "Pigments? read Pigment line. 44, for F1809" read 20.0 column 5, lines 12 and 37, for "YXSG", each occurrence, read XYSG line 64, for "4n-octoxy" read 41 n-octoxy line 66, for "(salol)" read (Salol) column 6, line 27, for "'carbowax" read Carbowax line 35, for "preferab 'y" read preferably column 8, line 20, for "respense" read response Signed and sealed this 9th day of April 1963.

(SEAL) Attest:

ESTON JOHN SON DAVID L, LADD Attesting Officer Commissioner of Patents 

1. AS A NEW ARTTICLE OF MANUFACTURE, A SMUDGE-RESISTANT PRESSURE-SENSITIVE TRANSFER ELEMENT OF THE CARBON PAPER TYPE DESIGNED FOR THE PLACING OF SMUDGE-RESISTANT IMAGES COMPRISING A FLEXIBLE FOUNDATION SHEET HAVING THEREON THREE MUTUALLY ADHERING LAYERS WHICH ARE SIMULTANEOUSLY LOCALLY TRANSFERABLE FROM THE FOUNDATION TO A COPY SHEET IN A SUBSTANTIALLY STENCILING MANNER IN RESPONSE TO A BELOW OR PRESSURE, THE MIDDLE LAYER BEING CHARGED WITH PIGMENT DESIGNED FOR AUTOMATIC SENSING, THE BASE LAYER ADJACENT THE SURFACE OF THE SHEET HAVING READILY RELEASABLE CONTACT THEREWITH AND CONTAINING A PIGMENT DESIGNED FOR MASKING THE PIGMENT OF THE MIDDLE LAYER OF SAID IMAGES, AND THE TOP LAYER BEING OF SMUDGE-RESISTANT CHARACTER AND HAVING PRONOUNCED ADHESIVENESS FOR SAID COPY SHEET. 